Reconstruction of paradigm shifts

There are many extensions of the basic attribute grammar formalism intended to improve its pragmatics, e.g. certain modularity concepts, remote access, object-orientation, templates, rule models and higher-order features. In the paper, a generic and formal approach to an effective and orthogonal reconstruction of the concepts underlying some extensions is described. The reconstruction is effective in the sense that the reconstructed concepts are presented as executable meta-programs. The approach to reconstruction is formal in the sense that the derived meta-programs modelling certain concepts can be analysed based on properties of the meta-programs, e.g. preservation properties. It is a generic approach because the meta-programming framework can be instantiated not only for attribute grammars but also for several other representatives of the declarative paradigm, e.g. natural semantics and algebraic specification. Thereby, concepts can be imported from and exported to other frameworks. Finally, the reconstructions are derived orthogonally in the sense that potential roles are first unbundled and then particular combinations of the roles can be investigated. The described meta-programming framework has been implemented in the specification framework of Λ∆Λ and it is used for reusable formal language definition based on attribute grammars and operational semantics.